http://www.junkfax.org/fax/action/getEven.html
Not sure if this part is real or not but found this interesting:
Step #4
If you want to take matters into your own hands and don't mind spending a bunch of hours to do that, you can sue in small claims court. I can tell you that small claims works. For example, I got 16 faxes from First Chartered Investments and after a 15 minute hearing, walked out with 16 judgments for $2,500 each, a total of over $40,000 (see FirstChartered.pdf). Here's how to do it:
How to get $2,500 per junk fax in small claims court
How to get $2,500 per junk fax (California only)
How to sue people (general legal tips)
How to sue in small claims court
Lawsuit tips and tidbits
Collection tips and tidbits